The invention relates to a device for introducing a defined amount of a second powder into a process container in which a first powder or a powder mixture is present. The device is provided in particular for charging small and minute amounts of powdered substances into larger process containers, in particular for admixing low amounts of powdered active pharmaceutical substances to main components already present in a process container, such as lactose or corn starch. The invention is particularly suited for containment applications of active substances and/or sterile applications.
According to the prior art, the addition of certain components into mixing containers is known to be carried out by simple pouring via an opening in the lid. For this purpose, a pocket-size metering device for pourable goods as described in the unexamined patent application DE 21 43 403 can be used. The hand-held metering device is used only for the metered dispensing of artificial sweetener due to the low precision of the device, although it was intended for powdered pharmaceuticals.
Another device for mixing a blend of pulverized constituents is described in DE 3 104 062 A1, for example. A second powder is introduced into the fluidized bed of a first powder. This is carried out under pressure by impinging the second pulverized constituent onto a deflection plate disposed within the fluidized bed for uniform distribution of the second constituent therein.
A metering device acting according to the principle of gravity is described in DE 2 917 189 B2, for example. For volumetrically metering free-flowing powders in batches using a storage container and a double piston metering unit comprising a piston rod having an upper piston and a lower piston, the lower piston of which can move away from the upper piston, the lower piston moves away from the upper piston during an upward movement of the piston rod and approaches the upper piston during the downward movement of the piston rod, whereby the volume of the constriction present between the upper and lower pistons increases to a predetermined extent during the upward movement and decreases to the predetermined metering volume during the downward movement before passing the dosing chamber.
Another option for adding is to carry out the charging via an opening in the lid by way of long mixing lances extending into the mixed bed.
DE 20 62 513 B2 describes a device for volumetrically metering free-flowing powder in batches, comprising a vertically disposed piston rod that is provided with a constriction as the feed control device. Metering devices of this type have the disadvantage of low precision in terms of the metered amounts of powder.
So as to meet a general requirement that is placed on pipe couplings, according to which each half of the coupling comprises a respective valve which can be opened when the coupling halves are properly joined to each other and which must be moved so as to be fully closed before the respective halves of the coupling can be separated from each other, EP 0 447 023 B1 describes a dry break coupling for lines having two valve flaps that can be actuated separately from each other.
DE 20 2009 018 738 U1 discloses an easy-to-detach coupling system for axially coupling two parallel flanges, in which the end faces of the two flanges are axially pressed against each other for coupling purposes, and in which two coupling halves comprise rotatably mounted closing flaps, which are seated against each other in a planar manner after the coupling has been established and can be opened together.
DE 4 342 962 C1 describes a device for coupling two containers which each have a connecting pipe neck, in which each of the pipe necks comprises a closing flap close to the end facing away from the container supporting the neck, the closing flap being essentially pivotable by 90° about a diameter of the pipe neck, the outside diameter thereof essentially corresponding to the inside diameter of the pipe neck.
An added substance metering device for a polyurethane plant for introducing a defined amount of a second substance into a process container in which a first substance or a substance mixture is present is known from DE 20 2005 015 569 U1, wherein the substance can be introduced into a cartridge 10 that is inserted into a holder and equipped with a quick-action coupling and can be emptied by way of a delivery piston 26.